Why Do Cats Vomit? Understanding the Causes and What to Do

It’s a scene familiar to many cat owners: the sudden retching sound, followed by the unpleasant sight of cat vomit on your rug. While occasional vomiting might seem like a normal part of cat ownership, frequent or severe vomiting is a sign that something isn’t right with your feline friend. Understanding Why Do Cats Vomit is crucial for every cat owner to ensure their pet’s health and well-being. This guide will explore the common causes of vomiting in cats, what different types of vomit might indicate, and when it’s time to seek veterinary help.

Decoding Cat Vomit: What Does It Mean?

The appearance of your cat’s vomit can offer initial clues, although it’s not a definitive diagnosis. Observing the characteristics can help you provide valuable information to your veterinarian. Here’s a breakdown of what different types of cat vomit might suggest:

Yellow Vomit: This is typically bile, a digestive fluid produced by the liver. Yellow vomit often indicates an empty stomach and can occur if a cat hasn’t eaten in a while. However, it can also be a sign of liver issues or simply that your cat ate something yellow.
Clear Vomit: Clear vomit can be either regurgitation from the esophagus or stomach fluids from an empty stomach. Regurgitation often happens shortly after eating and is expelled with minimal effort, unlike vomiting which involves abdominal contractions.
White, Foamy Vomit: Similar to clear vomit, white and foamy vomit usually points to regurgitation or stomach secretions when the stomach is empty. It’s not necessarily indicative of a serious problem but could suggest mild irritation or an empty stomach.
Blood in the Vomit: The presence of blood in cat vomit is always a cause for concern. Bright red blood indicates fresh bleeding, potentially from the mouth, esophagus, or stomach lining.
Coffee-Ground Vomit: Vomit that resembles coffee grounds suggests digested blood. This is a sign of bleeding in the stomach, often associated with stomach ulcers. It requires prompt veterinary attention.
Brown, Smelly Vomit: Brown vomit can result from bleeding in the upper gastrointestinal tract, where blood has been partially digested. It can also simply mean your cat ate something brown and, well, smelly. The odor can sometimes be particularly foul if it originates from further down the digestive tract.
Undigested Food in the Vomit: Seeing undigested food in vomit shortly after a meal might indicate that the food hasn’t properly left the stomach. This can be due to food intolerances or allergies, gastrointestinal obstructions, or general irritation of the upper digestive tract. However, if a cat vomits undigested food many hours after eating, especially if they haven’t eaten since, it could point to a more serious issue like an obstruction or a motility disorder where the stomach isn’t emptying correctly.

Alt text: Concerned cat owner observing their sick cat who is about to vomit, highlighting the common worry about feline vomiting.

Common Causes of Vomiting in Cats

Understanding why cats vomit requires considering a wide range of potential causes. Here are some of the most frequent reasons behind feline vomiting:

Dietary Indiscretion: Cats are curious creatures and sometimes eat things they shouldn’t, from garbage and spoiled food to plants and insects. This can lead to stomach upset and vomiting.
Hairballs: A classic cause of cat vomiting, hairballs occur when cats groom themselves and ingest fur. Sometimes, this fur accumulates in the stomach and is expelled through vomiting.
Food Sensitivities and Allergies: Just like humans, cats can develop sensitivities or allergies to certain food ingredients. These reactions can manifest as vomiting, diarrhea, and skin issues.
Infections: Viral, bacterial, and parasitic infections can all cause vomiting in cats. Common culprits include feline panleukopenia virus, feline calicivirus, and gastrointestinal parasites like worms.
Toxins and Poisons: Cats can ingest various toxins, from household cleaners and medications to poisonous plants and antifreeze. Toxin ingestion often leads to vomiting, among other serious symptoms.
Systemic Diseases: Several underlying health conditions can cause chronic vomiting in cats. These include kidney disease, liver disease, hyperthyroidism, diabetes, pancreatitis (inflammation of the pancreas), and inflammatory bowel disease (IBD).
Gastrointestinal Obstructions: Foreign bodies, such as string, toys, or bones, can become lodged in a cat’s digestive tract, causing a blockage. Obstructions are serious and often require surgical removal.
Medications: Certain medications can have vomiting as a side effect in cats. Always discuss potential side effects with your veterinarian when starting a new medication for your cat.

When to Worry: Signs Vomiting is Serious

While occasional vomiting might be benign, it’s crucial to recognize when it signals a more serious problem. Seek veterinary attention immediately if your cat exhibits any of the following signs along with vomiting:

Frequent or Projectile Vomiting: Vomiting multiple times in a short period or forceful, projectile vomiting is concerning.
Lethargy or Weakness: If your cat is unusually tired, weak, or unresponsive, it could indicate dehydration or a serious underlying condition.
Loss of Appetite: Refusal to eat, especially for more than 24 hours, alongside vomiting, is a red flag.
Dehydration: Signs of dehydration include dry gums, sunken eyes, and decreased skin elasticity (skin tenting).
Blood in Vomit (Hematemesis) or Coffee-Ground Vomit (Melena): As mentioned earlier, blood in vomit is always a serious sign.
Abdominal Pain: If your cat seems painful in the abdomen, resists being touched there, or is in a hunched position, it could be experiencing abdominal distress.
Weight Loss: Unexplained weight loss, especially in conjunction with chronic vomiting, warrants veterinary investigation.
Vomiting Undigested Food Many Hours After Eating: This can indicate a problem with stomach emptying or a potential obstruction.

Alt text: Veterinarian gently examining a cat on an examination table, highlighting the importance of professional veterinary care for diagnosing cat vomiting.

Diagnosing the Cause of Cat Vomiting

To accurately determine why a cat is vomiting, a thorough veterinary examination is essential. Your veterinarian will start by gathering information about your cat’s history and the vomiting episodes. Be prepared to answer questions such as:

Was the cat exposed to plants or potential toxins?
When did the vomiting start and how often is it happening?
What is your cat’s normal diet?
Does your cat go outdoors, and if so, does it hunt or scavenge?
What does the vomit look like (describe color, consistency, contents)?
Is your cat currently on any medications?
Is your cat also experiencing diarrhea?
Is your cat eating and drinking normally?
When does the vomiting occur in relation to eating or other activities?
Has your cat lost weight recently?
Is your cat drinking or urinating more than usual?
Does your cat play with string or similar objects that could be ingested?

Following the history, a complete physical examination will be performed. The veterinarian will check for signs like abdominal pain, masses, foreign bodies (such as string under the tongue), weight loss, heart murmurs, enlarged thyroid gland, and fever. Based on these findings, further diagnostic tests may be recommended, including:

Abdominal X-rays: Radiographs can reveal abnormalities in organ size and shape, foreign bodies, tumors, constipation, and other issues not detectable during a physical exam.
Blood Work and Urinalysis: Blood tests can assess organ function and detect conditions like diabetes and hyperthyroidism. A urinalysis, performed alongside blood work, helps diagnose kidney disease, urinary tract infections, and diabetes. Blood work can also provide clues about toxin exposure.
Barium Study: If X-rays are inconclusive, a barium study (where the cat swallows barium, a contrast agent) can help visualize the gastrointestinal tract and identify obstructions or motility problems.
Ultrasound: Abdominal ultrasound provides detailed images of internal organs, allowing for assessment of organ architecture and guided tissue sampling for diagnosis.
Endoscopy: Endoscopy involves inserting a flexible scope with a camera into the stomach, upper intestines, or colon. It allows direct visualization of the lining, detection of foreign bodies not visible on X-rays, and the collection of biopsies.
Exploratory Surgery: In cases of persistent vomiting where other diagnostics are inconclusive, exploratory surgery may be necessary. Surgery allows for a complete examination of the abdominal organs and the collection of full-thickness biopsies from the intestines, stomach, liver, pancreas, and lymph nodes. It is also used to remove foreign bodies.

Treatment Options for Vomiting Cats

Treatment for vomiting in cats is highly dependent on the underlying cause. It’s crucial to consult with your veterinarian for a proper diagnosis and tailored treatment plan. However, general treatment approaches may include:

Fluid Therapy: Dehydration is a common consequence of vomiting. Fluid therapy, either subcutaneous (under the skin) or intravenous (IV), is often administered to restore hydration and support recovery. IV fluids are typically used for more severely dehydrated cats.
Anti-emetic Medications: Anti-vomiting medications help control vomiting, reduce fluid loss, alleviate abdominal discomfort, and encourage appetite.
Stomach Protectants: Medications like Pepcid (famotidine) or sucralfate may be used to protect the stomach lining, although their effectiveness is debated. They generally don’t cause harm.
Dietary Changes: Diet plays a significant role in managing vomiting. For acute cases, a temporary switch to a highly digestible diet (like prescription gastrointestinal diets or bland homemade options like plain cooked chicken – without skin or bones – in small amounts and for short periods only) can be beneficial. For chronic vomiting, dietary trials with prescription hypoallergenic or limited-ingredient diets are often used to rule out food sensitivities or manage inflammatory bowel disease.
Prednisone: In cases of inflammatory bowel disease (IBD), prednisone, a corticosteroid, may be prescribed to reduce inflammation. However, prednisone has potential side effects and should only be used under veterinary guidance after appropriate diagnostics, as it can worsen certain conditions.

Understanding why cats vomit is the first step in addressing this common feline issue. By observing your cat’s vomit, recognizing warning signs, and seeking timely veterinary care, you can help ensure your cat receives the appropriate diagnosis and treatment to get back to their healthy, happy selves.